Safety device for electric-lamp bulbs



Dec. 9, 1930. P. s. ARGUELLES SAFETY DEVICE FOR ELECTRIC LAMP BULBS Filed llay 17, 1929 2 Sheets-Sheet 1 F- 6- Qv/giiel'a uven'r 'k Dec. 9; 1930. P, 5, ARGUELLES 1,784,167

SAFETY DEVICE FOR ELECTRIC LAMP BULBS Filed May 17, 1929 2 Sheets-Sheet 2 f. 6f mile/;

Patented Dec. 9, 1930 UNITED STATES "PATENT PAULINO canon IARGFELLES, or ILA FELGUERA, SPAIN SAFETY DEVICE FOR ELECTRIC-Lamar BULBS Application filed Kay 17, 1928, Serial No. 363,826, and in Spain October 23, 1928.

1o lamps having screwed caps wherein a metallic pin or like member attached to the cap of the bulb can be sprung inwardly for insertion in the socket, but is subsequently adapted to be engaged in an inaccessible position within the socket positively preventing reverse rotation and withdrawal of the lamp.

In the accompanying drawings Figure 1 is an elevation of one form of the invention,

Figure 2 is a plan View of the same,

Figures 3 and 4 are elevation and plan views respectively of a second modification,

Figures 5 and 6 show respectively in plan an elevation of a modified form of the safety device in position in the holder.

Referring now to Figure l of the drawing, in the outer part of the cap or shell of the bulb and in prolongation of the last spiral ring of the thread thereof, a metallic pin or tcnon A which can be of wire or any other convenient metal or forged iron, is soldered by one of its two extremities to the right and in the same direction as the thread, the other left extremity being left free and 23 extending sufficiently forwardly of the thread. In Figs. 3 to 6 twopins B and C are connected to the shell instead of one.

Then introducing the threaded cap or shell of the bulb into the threaded sleeve forming a socket D of the support or holder E of the electric lamp fixture, the pins or tenons B and Oof the safety device, which are normally directed outwardly under Figures 5 and 6 the free ends of the pins or tenons of the safetydevice are released from thethreaded hollow body of the socket and owing to spring action enter one of the two hollow spaces F provided at the inner part 5 of the support or holder E, securing thus the bulb to the support in such a manner that it cannot be removed owing to the fact that the said safety device formshenceforth an' obstacle preventing removal of the bulb by engaging the wall of the holder and obstructing reverse rotation. In this connection it is to be understood that spaces F are provided between the opposed arms G which join the socket D to the attaching part'of the support or holder.

When it is desired to take off the bulb once thus secured by the above described safety device, it is necessary to break the said .bulb and remove the exterior rings of the holding body, the pins or tenons being thus disclosed, so' that it will be easy to cut them off by means of small tongs or nippers; the thread can be removed without any difliculty and a new bulb can be replaced in the support or holding body of the electric lamp.

Claims:

1. A safety device for an electric lamp bulb including in combination, a holder embodying an attaching portion, a threaded sleeve, spaced arms joining the sleeve to the attaching portion and coacting with the sleeve and attaching portion to form a receiving socket, a lamp bulb including a threadedshell, and a spring member secured to and forming a continuation of the thread of the shell at the outer end thereof adapted to be screwed with the shell into the sleeve and to spring outwardly and impinge against one of the arms whereby to lock the lamp bulb in the holder.

2. An arrangement as claimed in. claim 1, wherein the arms of the holder provide two opposed spaces, and wherein two spring members are arranged at opposite points on the shell of the bulb for engaging in the spaces provided between the said arms.

3. A locking device for bulbs of electric lamps having thread-ed shells, including a metallic spring member attached to the outer end of the shell of the bulb and adapted to be sprung inwardly for insertion in the socket of an electric fixture and subsequently adapted to be engaged in an inaccessible position in the socket for positively preventing reverse rotation and Withdrawal of the lamp bulb.

In testimony whereof I affix my signature.

'PAULINO GARCIA ARGUELLES'. 

